In recent years, the concrete industry has strongly demanded improved durability and strength of concrete structures, and this has created a great need to reduce the unit amount of water. Notably, many polycarboxylic acid-based dispersants for cement have been proposed because these dispersants exhibit higher water-reducing ability than other conventional dispersants for cement such as naphthalene-based dispersants.
One example of such conventional polycarboxylic acid-based dispersants for cement is a copolymer prepared from a specific ratio of an unsaturated carboxylic acid monomer and an unsaturated alcoholic monomer (for example, Patent Document 1). A copolymer obtained by polymerizing an unsaturated polyalkylene glycol ether monomer having a chain of a specific length and an unsaturated monocarboxylic acid monomer has also been proposed as a copolymer for admixtures for cement which exhibits high dispersibility even when used in a small amount (for example, Patent Document 2). Another proposal is for a method for producing a copolymer of an unsaturated polyalkylene glycol ether monomer and an unsaturated monocarboxylic acid-based monomer which provides a copolymer that can improve the quality of cement compositions such as mortar and concrete when used as an admixture for cement (for example, Patent Document 3).
Patent Document 1: JP 04-68323 B (p. 1-2)
Patent Document 2: Japanese Patent No. 3683176 (p. 1-2)
Patent Document 3: JP 2008-106238 A (p. 1-4)